Lift chain connector

ABSTRACT

A clamp for securing a lift hook or the like to a roller chain. Two identical clamp members have grooved jaws which engage and interfit with the side edges of the 8-shaped side plates of two or more roller chain links. Screws hold the clamp together and extend through the chain link openings. The opposite end of the clamp is pivotally connected to a lift hook by a pivot pin at right angles to the chain pins.

nited States Patent Pruitt [451 ar. 2, W72

[54] LIFT CHAIN CONNECTOR 2,435,328 2/1948 Smith ..294/82 [72] inventor: Duns L. Pruitt, 209 N. Park St., Martin- Primary Examine, Evn Bhmk Svlnev 4615' Assistant Examiner-J. Kenneth Silverman [22] Filed: May 25, 1970 Attorney-Trask, Jenkins & Hanley [2 I] Appl. No.: 40,256 [5?] ABSTRACT A clamp for securing a lift hook or the like to a roller chain. [52] "294/32 Two identical clamp members have grooved jaws which en- [51] In Cl 566C 1/34 gage and interfit with the side edges of the 8-shaped side plates of two or more roller chain links. Screws hold the clamp [58] meld Search "294/82 59/87 287/76 together and extend through the chain link openings. The op- 287/103 24/243 5 posite end of the clamp is pivotully connected to a lift hook by a pivot pin at right angles to the chain pins. [56] Reierences Cited UNITED STATES PATENTS 6 Claims, 3 Drawing Figures 894,223 7/1908 Nelsen "59/87 r PATENTEDMARZB I972 3,652,116

lmleiai if INVENTOR. DANA L. PRU l TT QZBLAZWV/LZ? ATTORNEYS LIFT CIIAIN CONNECTOR SUMMARY OF THE INVENTION This invention relates'to a clamp for securing a lift hook or the like to a roller chain.

Roller chain is especially useful as the load lifting element of portable hoists but heretofore it has been difficult to secure a hook or other load-engaging element to the end of such chain. The present invention provides a simple and convenient clamp for this purpose.

By roller chain" is meant chain composed of pairs of 8- shaped side plates arranged in overlapping relation with the successive pairs connected by pins through holes in their overlapping portions. The pins commonly carry rollers between the side plates, but such rollers are not necessarily present for purposes of the present invention.

The clamp of the present invention is formed by two identically shaped members which are fastened together. The lower portion of the clamp forms a yoke for connection to a lift hook or the like by a pivot pin at right angles to the chain pins. The upperportion of the clamp comprises jaws with cross-grooves formed therein. The jaws are adapted to receive more than one link of the roller chain, with the 8-shaped side plates of such chain. disposed perpendicularly to the jaw faces. The grooves in the jaws interfit with the curved edges of the side plates, and the jaws are clamped together against such curved edges by screws or other fasteners, at least one of which desirably passes through the chainlink openings. The clamp is thus held securely to one end of the roller chain for purposes of connecting it to a hook or other load engaging element.

BRIEF DESCRIPTION OF THE DRAWING The accompanying drawing illustrates the invention and shows a preferred embodiment. In such drawing:

FIG. 1 shows a clamp secured to a roller chain and connected to a lift hook;

FIG. 2 is a section taken along the line 2-2 of FIG. 1; and FIG. 3 is a section taken along the line 3-3 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT The clamp shown in the drawing secures a lift hook 12 to a roller chain 13 which may constitute the load lifting element of a hoist. The roller chain 13 is formed of pairs of 8-shaped side plates 14, with successive pairs overlapping and connected by pins 15.

The clamp 10 is formed by two identically shaped clamping members 16 each of which has a jaw portion 18 with crossgrooves therein shaped to engage 'and interfit with the curved side edges of at least two pairs of 8-shaped side plates 14 of the chain. The clamp members are clamped together by a large main screw 17 at the base of the jaws 18 and by two smaller screws 28 which extend through the jaws and through the link opening of a chain clamped therein. The screws 17 and 28 each pass through smooth openings in one jaw, and are threaded into threaded openings in the other jaw. Their heads are desirably countersunk in the first jaw. The parts are so arranged that the jaws 18 tightly grip the link sideplate edges and securely connect the clamp to the chain.

The opposite end portions 22 of the clamp members 16 are shaped to form a yoke for connection to lift hook 12 and have openings therethrough to receive a pivot bolt 24. The lift hook 12 is carried by a swivel member 25 having a connector tongue 26. This is received in the yoke formed by the ends 22 of the clamp members, and is secured thereto by the bolt 24. The lift hook is thus connected to the clamp 10 on a pivot axis at right angles to the pins of the chain 13 so that it is free to swing in a plane parallel to the planes of the jaws 18. The hook may also rotate in its swivel connector 25 as indicated by the arrow in FIG. 1.

The clamp 10 is readily attached to a chain by a simple operation and forms a secure connection between the chain and the hook. It requires only two clamp arts, which are ldentlcal except only that one contains threa ed holes and the other smooth holes.

I claim:

1. A clamp for securing a lift hook or the like to a roller chain having a series of links formed of pairs of spaced 8- shaped side plates interconnected by pins, comprising a pair of clamping members adapted to be clamped on the chain and to grip its side plates edgewise, said members forming jaws having a plurality of cross-grooves shaped and positioned to engage and interfit with the edges of the side plates of at least one chain link, said members having end portions arranged for connection to a lift hook or the like, and at least one fastening member for fastening the clamping members together and positioned to extend through a chain link clamped between said jaws.

2. A clamp as set forth in claim 1 wherein both of said pair of clamping members are identically shaped.

3. A clamp as set forth in claim 1 wherein a lift hook or the like is pivotally connected to said end portions on a pivot axis at right angles to the pins of a chain clamped therein so as to be able to swing in a plane parallel to the planes of said jaws.

4. A clamp as set forth in claim 3 wherein a main fastener fastens said clamping members together and two fastening members extend through said jaws in position to pass through chain links clamped between said jaws.

5. A clamp as set forth in claim 4 wherein each of said fasteners passes through an opening in one of said clamping members and is threaded into an opening in the other of said clamping members.

6. A clamp as set forth in claim 1 in combination with a lift hook or the like connected to said end portions and a roller chain having the side plates of at least one link thereof clamped edgewise between said jaws. 

1. A clamp for securing a lift hook or the like to a roller chain having a series of links formed of pairs of spaced 8-shaped side plates interconnected by pins, comprising a pair of clamping members adapted to be clamped on the chain and to grip its side plates edgewise, said members forming jaws having a plurality of cross-grooves shaped and positioned to engage and interfit with the edges of the side plates of at least one chain link, said members having end portions arranged for connection to a lift hook or the like, and at least one fastening member for fastening the clamping members together and positioned to extend through a chain link clamped between said jaws.
 2. A clamp as set forth in claim 1 wherein both of said pair of clamping members are identically shaped.
 3. A clamp as set forth in claim 1 wherein a lift hook or the like is pivotally connected to said end portions on a pivot axis at right angles to the pins of a chain clamped therein so as to be able to swing in a plane parallel to the planes of said jaws.
 4. A clamp as set forth in claim 3 wherein a main fastener fastens said clamping members together and two fastening members extend through said jaws in position to pass through chain links clamped between said jaws.
 5. A clamp as set forth in claim 4 wherein each of said fasteners passes through an opening in one of said clamping members and is threaded into an opening in the other of said clamping members.
 6. A clamp as set forth in claim 1 in combination with a lift hook or the like connected to said end portions and a roller chain having the side plates of at least one link thereof clamped edgewise between said jaws. 